At one time it was thought(still is?) that we live in a closed universe? So if we live in a closed universe we might try to get a picture of this space by thinking of the space S^3? remember, S^1 surface of a 2 dimensional ball, S^2 surface of a 3 dimensional ball, S^3 surface of a 4 dimensional ball, S^4 surface of a 5 dimensional ball. Let us not forget time. In a closed big bang universe can time be thought of as a big circle if we identify beginning and end points? If so can spacetime of a closed universe be thought of as the surface of a 5 dimensional ball? Thank you for any thoughts.